Improve applyCheck and TestAccount test utilites.

[dmkozh]

Description

applyCheck now properly closes the ledgers. This both improves the test coverage and prepares us for the future changes that may alter the transaction processing flow. This also avoids testing unrealistic scenarios where invalid transactions were applied to ledgers: these scenarios created wrong expectations, that ultimately ended up hiding a change in protocol behavior (#5431)

TestAccount now always loads the sequence number from the ledger, because transactions that failed validation no longer cause a sequence number bump. Doing this by default is more convenient and straightforward, and also it's less error prone. There is only a handful of tests that create multiple transactions per source account (to ensure it fails validation, or for the legacy protocols) and these manage seq nums manually. Load generation machinery now uses its own CachedTestAccount that has the old caching logic, which is relevant for pre-generating transactions.

Additionally, enforce transaction validation when closeLedger is done with strictOrder. Previously this skipped tx validation, which resulted in tests that would silently drop transactions. This hardens the new tests that need to apply transactions in the same ledger in strict order in order to realistically cover scenarios when transaction is invalidated at apply time by a different transaction.

Checklist

• Reviewed the contributing document
• Rebased on top of master (no merge commits)
• Ran clang-format v8.0.0 (via make format or the Visual Studio extension)
• Compiles
• Ran all tests
• If change impacts performance, include supporting evidence per the performance document

[Copilot]

Pull request overview

Updates transaction test utilities to use realistic ledger-close behavior and ledger-backed sequence numbers.

Changes:

• Reworks applyCheck and related transaction tests.
• Updates TestAccount and transaction generation sequence handling.
• Adjusts sponsorship, fee-bump, path-payment, Herder, and Soroban tests.

Reviewed changes

Copilot reviewed 22 out of 22 changed files in this pull request and generated 6 comments.

Show a summary per file

File	Description
src/transactions/test/TxEnvelopeTests.cpp	Models apply-time transaction invalidation.
src/transactions/test/SponsorshipTestUtils.cpp	Builds transactions immediately before closing ledgers.
src/transactions/test/RevokeSponsorshipTests.cpp	Removes manual sequence rollback.
src/transactions/test/PathPaymentTests.cpp	Validates malformed transactions without applying them.
src/transactions/test/PathPaymentStrictSendTests.cpp	Tests ordered, apply-time failures.
src/transactions/test/ParallelApplyTest.cpp	Guards unavailable historical protocols.
src/transactions/test/InvokeHostFunctionTests.cpp	Updates sequence and execution-cost expectations.
src/transactions/test/FeeBumpTransactionTests.cpp	Exercises fee bumps through ledger close.
src/transactions/test/ClaimableBalanceTests.cpp	Uses realistic application and fee accounting.
src/transactions/test/BumpSequenceTests.cpp	Captures current bad-sequence behavior.
src/test/TxTests.h	Makes applyCheck pointer input const.
src/test/TxTests.cpp	Reimplements application through ledger close.
src/test/TestUtils.cpp	Tracks sequences for generated transactions.
src/test/TestExceptions.h	Adds revoke-sponsorship exceptions.
src/test/TestExceptions.cpp	Maps revoke-sponsorship failures to exceptions.
src/test/TestAccount.h	Exposes cached sequence state.
src/test/TestAccount.cpp	Reloads sequence state from the ledger.
src/simulation/TxGenerator.h	Adds explicit sequence parameters.
src/simulation/TxGenerator.cpp	Supports caller-provided sequences.
src/simulation/LoadGenerator.cpp	Revises synchronization and retry bookkeeping.
src/herder/test/TxSetTests.cpp	Supplies explicit sequential transaction numbers.
src/herder/test/HerderTests.cpp	Updates sequence and surge-pricing scenarios.

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[Copilot]

Pull request overview

Copilot reviewed 65 out of 83 changed files in this pull request and generated 5 comments.

Suppressed comments (2)

src/transactions/test/ClaimableBalanceTests.cpp:883

• This derives the ID from the account's current ledger sequence, but the balance created by the following transaction is keyed with that transaction's sequence (current + 1; see CreateClaimableBalanceOpFrame.cpp:316-318). The claim therefore targets a nonexistent balance and breaks the create-and-claim-in-one-transaction case. Keep the explicit next sequence when computing the ID.
  src/herder/TxSetFrame.h:139
• Add the missing space between the identifier and “forces.”

[Copilot]

Pull request overview

Copilot reviewed 65 out of 83 changed files in this pull request and generated 1 comment.

Suppressed comments (4)

src/transactions/test/BumpSequenceTests.cpp:164

• Fix the typo in this newly added explanation: “validaition” should be “validation.”
  src/simulation/TxGenerator.h:116
• The phrase “per account it once” is ungrammatical; this should say “per account at once.”
  src/herder/TxSetFrame.h:122
• Add the missing space after the inline code span so the generated documentation reads correctly.
  src/herder/TxSetFrame.h:139
• Add the missing space after the inline code span so this overload's documentation reads correctly as well.

[Copilot]

Pull request overview

Copilot reviewed 66 out of 84 changed files in this pull request and generated no new comments.